Calcutta, June 4 : Calcutta, June 4: The stalemate at Wockhardt Hospital and Kidney Institute took a violent turn on Monday. Local goons masquerading as unionists pulled Institute staff out of their car and beat up two of them. The incident occurred around 5 pm, during change of shift at the renal treatment centre on Rashbehari Avenue. Seven staff members, including two women, were dragged out of the car just as they were leaving the Institute. All five men were roughed up, with Satyen Hati and Shyam Mandal being picked out for special treatment. The two had to be hospitalised, said M.K. Singh, officiating as deputy commissioner (south). On Monday evening, seven agitators were arrested in connection with the attack at Wockhardt. There has been trouble at the Institute since May 28, three days after the hospital management decided not to renew the services of two contractors for "poor quality of work". The two contractors supplied securitymen and general-duty attendants to the hospital. Trinamul Congress leaders then jumped into the fray, supporting the agitators, who tried to prevent patients and staff from entering the hospital and threatened them with unsavoury consequences if they dared attend to their duties. The hospital management has tried to maintain normalcy within the hospital. Patients are being admitted and treated, and operations conducted as usual. The management has received its share of cooperation from members of the staff who have braved threats for the past eight days to keep the hospital open and functioning. But with the agitators, who have put up Trinamul flags near the hospital gates, carrying out their threat on Monday evening, the crisis at the centre has deepened. "The attackers are believed to be men owing allegiance to former Congress councillor Tulsi Mukherjee," added a senior police officer. Both the Trinamul trade union wing, the Inttuc, and the Intuc have been quick to try and distance themselves from the Wockhardt episode. Inttuc leader and local MLA Sobhandeb Chattopadhyay denied any involvement of his men in the agitation. "I went there (to the hospital) one day as the local MLA and not as any union leader," he added. Mayor Subrata Mukherjee, also Intuc chief, claimed his union had nothing to do with the trouble at the centre. He also expressed concern over the piling up of garbage inside the hospital, the agitators having prevented Calcutta Municipal Corporation disposal vans from collecting the refuse from the troublespot. On Monday, three vans turned up at the Institute, but were not allowed to collect the garbage. Mukherjee said he would "wait another day" before seeking the help of the police in garbage collection. "The piling up of hospital waste cannot be allowed to go on, as it will endanger the well-being of patients," said the mayor.